It turns out it's hard out there for a narcissist — at least if he's a guy. A new study has found that men who are full of themselves may actually be stressed out by their own narcissism.

In a study published in PLoS One, researchers David Reinhard, Sara Konrath, William Lopez, and Heather Cameron gave 106 undergrads (79 women, 27 men) a 40-item Narcissistic Personality Inventory, in which they had to pick either narcissistic responses ("If I ruled the world it would be a better place") or non-narcissistic ones ("The thought of ruling the world frightens the hell out of me"). They subdivided the results into unhealthy narcissism — characterized by "entitlement" and "exploitativeness" — and healthy narcissism — associated with qualities like leadership and self-sufficiency (also vanity, though it's unclear why that's healthy). They also tested the subjects' saliva (using a technique amusingly called "passive drool") for cortisol, a hormone related to stress response. The researchers found that men with high levels of unhealthy narcissism also had higher cortisol levels. Unhealthily narcissistic ladies had higher levels too, but the effect was much smaller.

Higher levels of cortisol mean narcissistic dudes have a more active stress response, which could lead to cardiovascular problems — the study authors note that "future work might examine [whether] high narcissism in earlier life predicts poor health outcomes in later life." Though hanging out with a narcissistic person is certainly stressful, it's not obvious why narcissists themselves would be freaked out. Reinhard et al, however, note that previous research has shown that "narcissists are susceptible to a host of unrealistic self-views that are difficult and stressful to continuously maintain." Translation: convincing yourself that you're the most important person in the world is actually a lot of work. So why is this more stressful for men? The study authors write,

Perhaps females can escape more severe physiological consequences of narcissism because there are different expectations for their roles in society. Female gender roles promote behaviors that encourage women to value relationships and to seek and gain social support, which may lower their risks for chronic [stress]. In fact, female narcissism might be associated with different kinds of exploitative strategies than male narcissism. Perhaps female narcissists use "feminine" roles to their advantage and obtain both social and financial resources more indirectly.

Study coauthor Sara Konrath adds, "Given societal definitions of masculinity that overlap with narcissism — for example, the belief that men should be arrogant and dominant — men who endorse stereotypically male sex roles and who are also high in narcissism may feel especially stressed." This isn't carte blanche for ladies to act like assholes — they still might stress out the people around them. But the study's findings may point to a sort of poetic justice for male narcissists — acting like they're hot shit all the time may cause them pain, and even usher them into an early grave. Which seems like a pretty good argument for recognizing that the world doesn't revolve around you.